Water pump and method of assembly



J. s. SALETZKI ETAL 3,47 ,7

IATER FUN? AND METHOD OF ASSEMBLY Filed Oct. 4, 1967 MARVIN c. xeYs.

' JACOB s. SALETZKI INVENTOR.

6511 124 2 M We 2,,

United States Patent U.S. Cl. 103103 1 Claim ABSTRACT OF THE DISCLOSUREA water pump having an impeller and drive gear axially displaced on ashaft which is journalled on bearings which are preloaded as a result offorce exerted on the impeller by a spring which surrounds the shaft. Themethod of completely assembling the water pump and then inserting itintoits associated drive housing so that the pump can be installed in orremoved from the drive housing as a unit.

This invention relates to a water pump and method of assembling same. Inthe past, the assembly of water pumps has been expensive,time-consuming, and not amenable to easy repair. Generally when a waterpump is assembled or disassembled from its associated drive housing, theelements of the pump must be removed individually this results in a.time consuming efiiort and moreover, the elements of the pump aresubject to being lost.

The present invention therefore has for one of its objects the new andimproved method of assembling a water pump so that the pump can beentirely assembled prior to installation in the drive housing.

Another object of the present invention is the method of assembling awater pump so that it can be readily installed and removed from itsdrive housing while all of its parts remain in assembled relation.

Still another object of the present invention is the meth- 0d ofassembling a water pump so that the bearings in which the impeller shaftrotates are preloaded prior to installation of the pump in itsassociated drive housing.

It is yet another object of the present invention to provide a method ofasembling a water pump so that the entire pump including its drive gearare completely assembled and then located in the drive housing by meansof a pilot extension of the water pump with all parts of the water pumpremaining in proper position during the mating or demating of the waterpump and the drive housing.

Yet another object of the present invention is to provide a method ofassembling a water pump which will not structurally fail as a result oftorsional vibration.

A further object of the present invention is a water pump which can becompletely assembled prior to insertion in its drive housing.

A still further object of the present invention is a water pump whichhas bearings located intermediate the shaft and the water pump casingwhich are preloaded prior to assembly of the water pump and its drivehousing.

Other objects and advantages of the present invention will be madeobvious to those skilled in the art by the following description whenconsidered in relation to the accompanying drawing of which;

A longitudinal sectional view of water pump of the present invention isshown in the single figure.

Referring now to the drawing the main casing of the water pump is showngerenally at 10. Secured to one end of casing via means of seal 44 andsuitable bolts is a cylindrical casing 46. Fastened t0 the end of casing46 is an end plate 47. Mounted within the casing is an impeller 12,which is secured to shaft by furnace brazing. Previous designs have beenlimited in the amount of stress which the assembly could withstand. Inthe past, impellers have been secured to the shaft by means of tapers,shrink-fitting, etc. These prior art devices are more subject to failurethan the instant invention, however, due to torsional vibration. Hence,the new and improved means of securing the impeller to the shaft hasimproved the durability of the pump. Impeller 12 has blades 16 whichdirect the water through outlet port 14. A low pressure area is showngenerally at 18. Before the impeller 12 and shaft 20 are placed intocasing 10, a seal 24 comprised of ceramic ring 22 and rubber carrier 26is secured thereto. This design will place ceramic ring 22 incompression. The rubber carrier 26 could also be placed on the innerdiameter of the ceramic ring 22, however, this has a tendency to causethe ceramic to crack when it expands. By placing the rubber on theoutside, the ceramic seal 22 is in compression rather than tension,hence the ceramic will not crack. Another marked advantage of this sealarrangement is that carrier 26 and ring 22 can be easily serviced byremoving the shft and impeller assembly and installing new parts.Because the ceramic seal is not distorted at assembly, no lapping afterinstallation is required.

Main casing 10 has a flange 36 in which cup-like element 28 is pressfitted with an inwardly projecting shoulder 38. Mounted within element28 is a complementary ring shaped block 32 of carbon which has a highlypolished surface engaging ceramic ring 22. Helical spring member 42 ismounted within molding 40 and forces carbon block 32 into sealingengagement with ceramic ring 22. Moulding 40 may be manufactured from apolymer, leather or other similar synthetic material. This entiresealing arrangement prevents water directed by the impeller fromreaching shaft 20.

Main casing 10 has a pilot extension 50 into which casing 56 ispress-fitted. Lip seal is secured in casing 56 and rides on shaft 20 insealing engagement. Lip seal 80 prevents oil which is used to lubricatebearings 54 from passing into the impeller portion of the pump. Bearings54 are also secured Within pilot extension 50 by means of retainingplate 58 and bolts 60 pressing on outer race 84 and longitudinalextension 86 of gear 62 pressing on the inner race 82. Driving gear 62is secured to shaft 20 via means of key 64 and has teeth 66 which aredriven by any suitable power source such as a power-take-olf of adriving engine.

Shaft 20 is also journalled in bearings 68 which are secured withindrive housing 74. Bearings 68 are secured against gear 62 by means oflock washer 72 and lock nut 70. Main casing 10 is secured to drivehousing 74 by means of bolts 91. Seal 52 is provided to provide adequatesealing of casing 10 and pilot extension 50. Drive housing 74 isprovided with a face plate 88 which is secured to the engine block,power source, or other suitable power-take-off means by means of bolts76. A cutout 78 in pilot extension 50 is also provided as an oil orwater drainback. In the event oil passes by seal 80 or water passes byseals 24, 22 and 32, the liquids will drain through the port 78 ratherthan intermix the oil and water.

The present invention permits ease of assembly. Moreover, thisconstruction permits complete assembly of the water pump includingpreloading of bearing 54 prior to inserting it into drive housing 74. Toassemble the pump, cup-like element 28 would be press-fitted into flange36. Moulding 40 with spring 42 therein and carbon ring 32 would beinserted in cup-like element 28. Carbon ring 32 would then be insertedin cup-like element 28. A composite member comprising impeller 12, seal24, and shaft 20 is then placed through spring 42 with ceramic ring 22mated in sealing engagement with carbon ring 32. This arrangement allowsthe seal to be replaced without removing impeller 12 from the shaft.Casing 56 carrying seal 80is then press-fitted into sealing engagement"with shaft 20 and pilot extension 50. Bearing 54 is then secured againstshoulder 90 of the shaft by means of retainer plate 58 and longitudinalextension 86 of gear 62. Gear 62 is keyed to the shaft and secured bylock nut 70 which holds the inner race of bearing 68 against gear 62.This entire completed assembly can then be installed in drive housing 70and easily secured by means of bolts 91.

This method of assembly also facilitates pro-loading of bearing 54. Thiscan be understood by reference to the drawing. Spring member 42 willtend to force carbon ring 32 against ceramic ring 22 which is a part ofthe impeller. Since impeller 12 is brazed to shaft 20, shaft 20 and gear62 will tend to shift to the right as a result of the compression spring42 tending to force impeller 12 to the right as shown in the drawings.The longitudinal extension 86 of gear 62 only exerts force against innerrace 82 of bearing 54. Since outer .race 84 remains stationary and innerrace 82 tends to move with the shaft, the bearing is in a preloadedcondition. The bearing 68 is not preloaded and the outer race of bearing68 slips freely into drive housing 74 with a slight exertion of force.With the drive housing and main casing united, the entire pump may thenbe mounted on a power source such as a power-take-otf of an engine bymeans of bolts 76 wherein teeth 66 would mesh with the teeth of thepowertake-otf gearing. This would cause shaft 20 and hence impeller 12to turn and pump Water from inlet port 48 through outlet port 14 asdesired. Hence, a water pump and method of assembling same has beenprovided whereby the pump can be mounted on or removed from the drivehousing as a unit while maintaining its bearings in a preloadedcondition.

Since it is obvious that many changes and modifications can be made inthe above described details without departing from the nature and spiritof the invention, it is to be understood that the invention is notlimited to said details except as set forth in the appended claim.

We claim:

1. A water pump which can be completely assembled and integrally mountedas a unit in a drive housing comprising a main casing having a pilotextension extending radially therefrom, a cup-shaped element securedwithin said pilot extension, a first bearing mounted in said pilotextension, a shaft journalled in said first bearing, an impeller mountedon one end of said shaft having a ring seal integrally attached thereto,a first seal comprising a ring block of material mounted within saidcup-shaped element, a spring surrounding said shaft and in compressiveengagement with said ring block of material such that said ring block ofmaterial is placed in sealing engagement with said ring seal mounted onsaid impeller, a second seal mounted intermediate said first bearing andsaid cup-shaped element and in sealing engagement with said shaft, :1gear secured to said shaft having a portion in contact with the innerrace of said first bearing, a retainer plate secured to said pilotextension and in contact with the outer race of said first bearing, asecond bearing axially displaced from said first bearing and in whichsaid shaft is journalled, and locking means holding said second bearingin contact with said gear, said spring exerting force on said impeller,said shaft and said gear whereby said first bearing is preloaded priorto assembly of the water pump as a unit in a drive housing.

References Cited UNITED STATES PATENTS 1,47 6,781 12/ 1923 Vincent.3,001,517 9/ 1961 Baker et a1. 3,071,075 1/1963 Spring. 3,272,129 9/1966Leopold.

HENRY F. RADUAZO, Primary Examiner Us. or. X.R. 103-111; 230-133

